Lifting jack



Feb. 5, 1929. 1,701,134

a. B. WAlTE LIFTING JACK Filed Oct. 23, 1925 2 Sheets-Sheet 1 firm 11 21 Feb. 5, 1929.

G. B. WAIT E LIFTING JACK Filed Oct. 23, 1925 2 Sheets-Shut 2 glwventoz Patented Feb. 5, 1929.

TED Me's GUY B. WAITE, OF NEW YORK,IN. Y.

LIFTING JACK.

JA'pplication filedOctober 23, 1925. Serial No. 164,368.

This invention relates'to improvements in lifting-jacks, especially of the type which areused in garages for lifting motor vehicles, and hasfor its'particular objectsvto-provide a novel and more efficient jack which can be easily inserted under parts of an automobile that il'HIHgCIOSQ to the ground, and also to raise objects extremely high when desired. Qtherobjectsiof tlieiinvention. are to i provide a device a of this character avhichis simple in construction, strong, and readily manipulated. i a y These and other objects hereinafter set forth are attainedlby'the means illustrated in the accompanyingdrawing; in which:

Figure 1 is-a plan view of he improved Tack.

1 Figure 2 is a side elevation thereof.

Figure 3 is a detail perspective view showmg one of the liftingmrm-isupports.

Figure A; is a plan V lBWaOf- EL modified form of jaolgand i a a Figure 5 ista'sideelevation thereof, and

Figures 6, i7 and 8, are views showing other modified forms ofqjacks.

"Similar -.reference number-skin all figures' of the drawingsdesignatelike parts..v i y p In: carrying out the invention, there? is a provided an elongated truck formed iof longitudinally arrangedrside-beams l0:-and transverse -tie-.beams 11 :11, 11 .and 11, which; are of different lengths to a space the front ends of i the isidermenibers 1O ifurther apart than their rear-ends to form a triangular a5 shaped structuretas illustrated, :This triangular shape isithe preferred form, and the a members of the frame a are preferably formed of channelled metal to secure lightness and strength. The ends of member lliare extended beyond -the endsof-the members 10, and

in these extendedends are; pivoted the front- Wheels-12. At the rear end of the theme, in member 11 1", is pivotedtanother wheel 12, the same beinglocated-iat a central point between the ends ofsaid member 11" these wheels 12- and il2 iare preferablyof the caster-wheel type and with 1 them, a the jack can be shifted 7 from place-tqplace; with or without a load.

Transverse tie beam 11 also-has its ends extended beyondrthebeams 10 on eachside, wand on each of these extended ends: ismounted in any suitable manner a screw-jack prefer ably oft-the telescopic i-screwtype. Eachof rthesescrew jacks comprises ainut 13ifixed to itheibeam 112w main screw 13 engaging said lnut and an extension screw 13 which is adapted to engage an internal threadl-invthe bore of the main screw 13 Extension screws 13 are each provided with a head 14 which is adapted to engageand be fixed in airecess formed ina support 15 adapted; tosupport one end ofaitrunnion-bar 16, said her 16beting secured to t the support by loo ed straps 117 bolted to the topifacethereof. shistrunnion bar' l6 pivotally supports the lifting member composed of the llifting levers 116,

one adj went to each lifting-jack, said lifting levers being. pivoted intermediatetheir ends,

and are connected to the trunnion-hubby means of a yoke comprising apairofaloops 19 Wl1l0l1 are enclosed around the ,lrftmglevers and onopposite sidesiofthe-trunnionbar, andabearing-plate 20 connectingthe top sides ofsaidloops 19and adapted tobear upon the upper side of the trunnion-bar, as

clearly shown in Figure 3.

tically arranged screw 21 l pivoted at its,- lower end between the rear-ends ofthe franiebeams 10, i a screw nut 22, and n bearing block '23 mounted on transverse roller bars 124, which spanacross theireai iends of the liftingilevers and positioned on opposite sides of the screw it 21, said rollers being free to roll upon the upper face ofthe lifting'levers when they are being adjusted to different positions. At the front end of each liftingdever 18 is preferably mounted a serrated engagement .plate 25' which is adjustable up and .down .with

a respect to the upper face ofithezliftingdever by the screws 26.

.Mounted in transverse tie-beams 11 :is a

frame lifting screw 27,:the same beingiprovided at its lower end with a foot28 adapted to engage thefloor orground and thus elevate the rear-send of the jack-.tmck-whendesired. i

The front ends of the lifting-levers may also be provided with engaging plates '29 preferably secured to: the lower flanges ofthe lifting-levers and which are adapted ito be used whenit is desired to secure a :very low hold upon an article to be lifted.

The yoke connection of the liftlng-levers and the trunnion-bar is sufficiently loose to permitia lateral adjustment of the liftinglevers as indicatedin dotted lines in Figure 1.

It will be understood that the telescopic screw-jacks used for lifting the fulcrum-bar 16 may be of any well known construction with or without opera-ting gears as desired.

In the modified form shown in Figures 4 and 5, only one lifting lever 30 is used, which is operated in a similar manner to the levers 18 above described. This is a simplified form which can be carried without taking up much room.

In the modified form shown in Figures 6 and 7, a triangular frame is used similar to the one shown in Fig. 1, and also a tie'beam 11*. Only one ack 31 is used in this form and which is preferably located midway on the tiebeam 11 and supports the fulcrum bar 82 whose ends extend through the walls of the lifting levers 33, and are shown provided with limit heads 34 which may be removable. The rear ends of the lifting levers forming the lifting member are pivotally connected together at their rear ends, as shown at 35, to enable them to be shifted laterally when desired. It will be observed that in this form the lifting levers are located and operate within the outer side-bars of the supporting frame, which provides a more compact structure. The rear truck wheel 36 is positioned closely adjacent the rear end of the supporting frame, and the ground engaging screw 37 is preferably located at the end of the frame beyond the rear ends of the lifting member. The depressing screw 38 is pivoted to the frame at 89 and is also pivoted to the lifting member at 40, said screw being treaded through a nut 41 which carries the pivots 40, and said pivots are engaged in slots 42 in the walls of the lifting levers, whereby the pivots 4:0, and screw 38, can move longitudinally of the lifting levers to assume new pivot positions when the fulcrum rod 31 is adjusted either up or down.

Fig. 8 shows a form similar to that shown in Figs. 6 and 7, excepting that a relatively narrow rectangular frame 43 is used, and wherein the lifting levers 44: are centrally bowed and have their front and rear ends connected together. In this form also, only one jack 31 is used.

In use, the front end of the truck is run under the objectwhile the lifting levers are in the posit-ion shown in Figure 2- of the drawing, then the fulcrum rod screw or screws are adjusted to raise the engagement plates 25 into engagement with the load, and finally the nut 22 is screwec downwardly thereby depressing the rear ends of; the levers 18 and consequently lifting their front ends and the load. It is clearly obvious that the fulcrum of the lifting lovers can be adjusted either upwardly or downwardly to engage a high or low object to be lifted, and depending upon certain circumstances, either the fulcrum screw. or the depressing screw, or both, can

be used for lifting the object. The nut 22 can.

be provided with an operating handle, and a ratchet mechanism if desired. Screw 27 can be used to engage the ground or floor to act as a brake and prevent rolling of the wheeled frame, or it can be used to lift the rear end of the truck from off the ground to further elevate portions of the ack to secure a higher lift of the object when desired.

It is not necessary that the frame should be constructed in the manner shown, as details can obviously be changed without number. Nor is it necessary to use screws for raising or adjusting. It is quite evidentthat any form of well known means for raising or lowering can be employed in the place of the screws and screw-jacks shown.

Having thus fully described the invention, what is claimed is 1. A lifting-j ack, embodying a frame having a screw jack at opposite sides thereof, a pair of lifting members pivotally supported by said screw jacks and having front ends constructed to engage an object to be lifted and extended rear ends, and a single means connected to said supporting frame and constructed to engage both of said lifting mem bers at their rear ends and positively force them downwardly and. rock them upon the screw jacks.

2. A lifting-jack. embodying a supporting frame, a pair of lifting members havlng front ends constructed to engage an object to be lifted and extended rear ends, a fulcrum means for said members, a screw for each end of said fulcrum means to adjust the same, and a single operating means connected at the rear end of the supporting frame for depressing both of the rear ends of said lifting members.

3. A lifting-jack, embodying a frame having a screw jack at opposite sides thereof, a fulcrum bar extending across said frame and having its ends supported by said screw jacks, a pair of lifting members pivotally supported by said fulcrum bar and having front ends constructed to engage an object to be lifted and extended rear ends, and a single means connected to the rear end of said supporting frame and engaging both of the rear ends of said lifting members for operating the same forcibly downward.

4:. A lifting jack, embodying a supporting frame, a lifting means carried by said frame, a lifting member pivoted intermediate its length to said lifting means, and a depressing means for engaging a portion of the lifting means to rock the same on its pivots, said depressing means being slidably and pivotally connected to the lifting member.

5. A lifting-jack, embodying a supportingframe, a lifting member having one end constructed to engage an object to be lifted and an extended rear end, and a plurality of separate screw operating carried by said supporting frame and constructed to engage the extended rear end and also an intermediate portion of said lifting member in a manner to permit the rocking of the lifting member on either one of the screw operating means as a fulcrum when the other screw operating means is operated.

6. A lifting jack, embodying a support ing frame, a lifting member having one end constructed to engage an object to be lifted and an extended rear end, and a plurality of separate screw opera-ting means carried by said supporting-frame and constructed to engage the extended rear end and also an in termediate portion of said lifting member in a manner to permit the rocking of the lifting member on either one of the screw operating means as a fulcrum when the other screw operating means is operated, the extended rear end of the lifting member having a loose engagement with its screw operating means to permit a lateral movement between said members when being adjusted to different portions.

In testimony whereof I have aflixed my signature.

GUY B. WAITE. 

